One vertex per element, one color per generator, with an edge from x to x·s.
(1,2) involution — undirected(3,4)(5,6)(7,8)(9,10)(20,23)(24,26) involution — undirected(4,8)(6,9)(11,12)(13,17)(14,15)(16,18) involution — undirected(4,8)(5,10)(12,15)(16,17)(19,20)(21,24)(22,23)(25,26) involution — undirected(3,5)(4,9)(6,8)(7,10)(11,12)(13,16)(14,15)(17,18)(19,21,22,25)(20,24,23,26)(3,6,7,9)(4,5,8,10)(11,13,14,18)(12,16,15,17)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.